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         document.write("格式一");
         document.write("<br/>");
        for(var i=1; i<=9;i++){
            for(var j=1;j<=i;j++){
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            i*j>=10?document.write("&nbsp;"):document.write("&nbsp;&nbsp;");
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        document.write("格式二");
        document.write("<br/>");
         for(var i=9; i>=1;i--){
             for(var j=1;j<=i;j++){
             document.write(i+"*"+j+"="+i*j);
             i*j>=10?document.write("&nbsp;"):document.write("&nbsp;&nbsp;");
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         document.write("格式三");
         document.write("<br/>");
         for(var i=1;i<10;i++){
           
             for(var j=9;j>i;j--){
                document.write("&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;        ");
                   
             }for(j=i;j>0;j--){
                document.write(j+'*'+i+'='+i*j);
                i*j>=10?document.write("&nbsp;&nbsp;"):document.write("&nbsp;&nbsp;&nbsp;"); 
             
             }
             

            
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         document.write("格式四");
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             for(var j=9;j>i;j--){
                document.write("&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;        "); 
             }for(j=i;j>0;j--){
                document.write(j+'*'+i+'='+i*j);
                i*j>=10?document.write("&nbsp;&nbsp;"):document.write("&nbsp;&nbsp;&nbsp;"); 
             
             }
              
            
            
            

            document.write("<br/>");
             
         }

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